Tibial cutting guide assemblies and associated instrumentation for performing surgical methods

ABSTRACT

This disclosure is directed to tibial cutting guide assemblies for preparing a tibia for receiving an arthroplasty implant. Exemplary tibial cutting guide assemblies may include a tibial cutting block for making precise cuts in the tibia, and a slope setting pin for establishing a patient specific tibial slope. The tibial cutting guide assemblies allow for level resection while providing surgical control over internal/external rotation and varus/valgus alignment.

BACKGROUND

This disclosure relates to surgical devices, and more particularly toorthopedic surgical devices for performing arthroplasties.

Arthroplasty is an orthopedic surgical procedure performed to repair orreplace diseased joints. For example, total knee arthroplasty (TKA) maybe performed to treat patients with diseased knee joints. Specific toolsand instruments are required for preparing knee bones for receivingarthroplasty implants.

SUMMARY

A tibial cutting guide assembly according to an exemplary aspect of thepresent disclosure includes, among other things, a tibial cutting blockincluding a biasing clip, and a slope setting pin biased toward asurface of the tibial cutting block by the biasing clip.

In a further non-limiting embodiment of the foregoing tibial cuttingguide assembly, the slope setting pin is adjustably received within apin receiving slot of the tibial cutting block.

In a further non-limiting embodiment of either of the foregoing tibialcutting guide assemblies, the surface is an upper wall of a block bodyof the tibial cutting block that delineates a portion of the pinreceiving slot.

In a further non-limiting embodiment of any of the foregoing tibialcutting guide assemblies, a block body of the tibial cutting blockincludes a unitary, monoblock design and is made of a polymericmaterial.

In a further non-limiting embodiment of any of the foregoing tibialcutting guide assemblies, the tibial cutting block includes a firstcutting slot and a second cutting slot that is separated from the firstcutting slot by an interior wall of the tibial cutting block.

In a further non-limiting embodiment of any of the foregoing tibialcutting guide assemblies, a first fixation pin hole and a secondfixation pin hole extend through the tibial cutting block and open intothe first cutting slot.

In a further non-limiting embodiment of any of the foregoing tibialcutting guide assemblies, a third fixation pin hole extends through thetibial cutting block and opens into the second cutting slot.

In a further non-limiting embodiment of any of the foregoing tibialcutting guide assemblies, the biasing clip includes a first end portionintegrally formed with an inner wall of a front side of the tibialcutting block, a second end portion arranged adjacent to an inner wallof a tibial attachment side of the tibial cutting block, and an arcedcurvature between the first end portion and the second end portion.

In a further non-limiting embodiment of any of the foregoing tibialcutting guide assemblies, the biasing clip establishes a floor of a pinreceiving slot of the tibial cutting block, and further wherein theslope setting pin is movably received within the pin receiving slot.

In a further non-limiting embodiment of any of the foregoing tibialcutting guide assemblies, the slope setting pin includes an elongatedshaft including a distal section that includes a hook-shaped tip and apair of flat surfaces.

In a further non-limiting embodiment of any of the foregoing tibialcutting guide assemblies, the slope setting pin includes an elongatedshaft including a proximal section, a distal section, and a mid-section.The proximal section includes a first diameter that is smaller than asecond diameter of the mid-section.

An arthroplasty instrument set according to another exemplary aspect ofthe present disclosure includes, among other things, a tibial cuttingblock assembly, a varus-valgus alignment device, and at least twofixation pins.

A method of preparing a bone for receiving an arthroplasty implantincludes, among other things, positioning a slope setting pin of atibial cutting guide assembly within a joint space between a femur and atibia, securing a tibial cutting block of the tibial cutting guideassembly to the tibia with a first fixation pin, bending a portion ofthe slope setting pin away from the tibial cutting block, inserting asecond fixation pin through the tibial cutting block, and making a firstcut in the tibia through a first cutting slot of the tibial cuttingblock.

In a further non-limiting embodiment of the foregoing method,positioning the slope setting pin includes positioning a hook-shaped tipof the slope setting pin against a posterior surface of the tibia.

In a further non-limiting embodiment of either of the foregoing methods,prior to bending the portion of the slop setting pin, the methodincludes inserting a third fixation pin through the tibial cuttingblock.

In a further non-limiting embodiment of any of the foregoing methods,bending the portion of the slope setting pin includes bending a proximalsection of an elongated shaft of the slope setting pin, thereby alteringa position of a handle of the slope setting pin relative to the tibialcutting block.

In a further non-limiting embodiment of any of the foregoing methods,prior to bending the portion of the slop setting pin, the methodincludes inserting a drop rod of a varus-valgus alignment device throughthe tibial cutting block and adjusting a varus-valgus alignment of thetibial cutting block relative to the tibia via the drop rod.

In a further non-limiting embodiment of any of the foregoing methods,the method includes making a second cut in the tibia through a secondcutting slot of the tibial cutting block.

In a further non-limiting embodiment of any of the foregoing methods,the slope setting pin establishes a patient specific tibial slope whenpositioned in the joint space.

In a further non-limiting embodiment of any of the foregoing methods,the slope setting pin is biased against a surface of the tibial cuttingblock by a biasing clip of the tibial cutting block.

The embodiments, examples, and alternatives of the preceding paragraphs,the claims, or the following description and drawings, including any oftheir various aspects or respective individual features, may be takenindependently or in any combination. Features described in connectionwith one embodiment are applicable to all embodiments, unless suchfeatures are incompatible.

The various features and advantages of this disclosure will becomeapparent to those skilled in the art from the following detaileddescription. The drawings that accompany the detailed description can bebriefly described as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exemplary tibial cutting guide assembly of anarthroplasty instrument set.

FIG. 2 is a front view of a tibial cutting block of the tibial cuttingguide assembly of FIG. 1 .

FIG. 3 is a rear view of the tibial cutting block of FIG. 2 .

FIG. 4 is an end view of the tibial cutting block of FIG. 2 .

FIG. 5 is a cross-sectional view through section 5-5 of FIG. 2 .

FIG. 6 is a cross-sectional view through section 6-6 of FIG. 2 .

FIG. 7 is a perspective view of a slope setting pin of the tibialcutting guide assembly of FIG. 1 .

FIG. 8 is a front view of the slope setting pin of FIG. 7 .

FIGS. 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, and 19 schematicallyillustrate an exemplary method for preparing a bone for receiving anarthroplasty implant.

DETAILED DESCRIPTION

This disclosure is directed to tibial cutting guide assemblies forpreparing a tibia for receiving an arthroplasty implant. Exemplarytibial cutting guide assemblies may include a tibial cutting block formaking precise cuts in the tibia, and a slope setting pin forestablishing a patient specific tibial slope. The tibial cutting guideassemblies allow for a level resection while providing surgical controlover internal/external rotation and varus/valgus alignment. These andother features of this disclosure are discussed in greater detail in thefollowing paragraphs of this detailed description.

FIG. 1 illustrates a tibial cutting guide assembly 10 that may be usedto prepare a patient for the implantation of an arthroplasty implant,such as during an arthroplasty procedure. In an embodiment, the tibialcutting guide assembly 10 is part of an arthroplasty instrument set thatmay be used to prepare a patient's tibia and femur, such as by sizing,marking, and making numerous cuts in the tibia and the femur, forpreparing the knee joint for the implantation of one or more kneearthroplasty implants. However, the illustrated instruments are notlimited to uses associated with the tibia and femur and could haveadditional applications for preparing for the implantation of any totaljoint implant.

The tibial cutting guide assembly 10 may include a tibial cutting block12 and a slope setting pin 14. As further discussed below, the tibialcutting block 12 may be used for making precise cuts in a patient'stibia, and the slope setting pin 14 may be movably received within a pinreceiving slot 16 of the tibial cutting block 12 for establishing apatient specific tibial slope. The tibial cutting guide assembly 10 mayfurther provide for a level resection of the tibia while facilitatingsurgical control over internal/external rotation and varus/valgusalignment.

The tibial cutting block 12 of the tibial cutting guide assembly 10 ofFIG. 1 is further illustrated with reference to FIGS. 2-6 . The tibialcutting block 12 may include a block body 18 having a unitary, monoblockdesign that includes a tibial attachment side 20, a front side 22opposed to the tibial attachment side 20, a right side 24, and a leftside 26. In this embodiment, the right side 24 is oriented to thecruciate ligament while the left side 26 is oriented either medially orlaterally. Therefore, the tibial cutting block 12 may be used mediallyat the left tibia or laterally at the right tibia. A tibial cuttingblock for use laterally at the left tibia or medially at the right tibiawould be oriented as the mirror image of the tibial cutting block 12shown in FIGS. 2-6 .

The tibial attachment side 20 of the block body 18 may include aslightly arced curvature that mimics the curvature of the anteriorsurface of the proximal tibia. The front side 22 of the block body 18may also be slightly curved to facilitate handling of the tibial cuttingblock 12.

The pin receiving slot 16, a first cutting slot 28, a second cuttingslot 30, a first fixation pin hole 32, a second fixation pin hole 34,and a third fixation pin hole 36 may be formed through the block body 18and may extend in an anterior-posterior direction for penetratingthrough both the tibial attachment side 20 and the front side 22. Thepin receiving slot 16 has a length in the left-right direction (relativeto a patient) and is configured to receive the slope setting pin 14. Inan embodiment, the pin receiving slot 16 is located superior to, orvertically above, the first cutting slot 28.

The first cutting slot 28 has a length in the left-right direction andis configured as a capture for guiding a saw blade or other cutting toolthrough the block body 18 for making horizontal cuts in a tibia. Thesecond cutting slot 30 has a length in the superior-inferior directionand is configured as another capture for guiding a saw blade or othercutting tool through the block body 18 for making vertical cuts in thetibia. In an embodiment, the second cutting slot 30 is located axiallybetween the first cutting slot 28 and the right side 24 of the blockbody 18. An interior wall 25 of the block body 18 separates the secondcutting slot 30 from the first cutting slot 28 such that these slots donot intersect one another.

The first fixation pin hole 32, the second fixation pin hole 34, and thethird fixation pin hole 36 may establish anterior-posterior orientedchannels through the block body 18 and are each configured to allow forthe insertion of a fixation pin (not shown in FIGS. 2-6 ) fortemporarily fixating the tibial cutting block 12 to the tibia. The firstand second fixation pin holes 32, 34 may be positioned just above (i.e.,superior to) the first cutting slot 28 and may open into the firstcutting slot 28. The third fixation pin hole 36 may be positioned justbelow (i.e., inferior to) the second cutting slot 30 and may open intothe second cutting slot 30.

The first and second fixation pin holes 32, 34 may converge toward oneanother at an angle a (see FIG. 5 ) in the anterior-to-posteriordirection. In an embodiment, the angle α is between 10 and 30 degrees.In another embodiment, the angle α is between 15 and 25 degrees. In yetanother embodiment, the angle α is about 15 degrees. The angle α isdesigned help prevent the tibial cutting block 12 from being pulled awayfrom the tibia during use.

An alignment rod hole 38 (best shown in FIGS. 2 and 5 ) may be formedthrough the right side 24 of the block body 18. The alignment rod hole38 may include a length extending in the superior-inferior direction andis configured to receive a varus-valgus alignment device (not shown inFIGS. 2-6 ).

As best shown in FIGS. 4 and 6 , a biasing clip 40 may be integrallyformed as part of the block body 18. In an embodiment, the biasing clip40 establishes a floor of the pin receiving slot 16. The biasing clip 40may include a cantilevered design in which a first end portion 42 isintegrally formed with an inner wall 44 of the front side 22 of theblock body 18, and a second end portion 46 extends adjacent to an innerwall 48 of the tibial attachment side 20 but is unattached thereto. Thebiasing clip 40 may include an arced curvature between the first andsecond end portions 42, 46. Due at least in part to the cantilevereddesign and the arced curvature, the biasing clip 40 may induce a biasingforce for biasing the slope setting pin 14 toward a surface of the blockbody 18, thereby firmly securing the slope setting pin 14 within the pinreceiving slot 16 while still allowing for movement and adjustability(e.g., internal/external rotation) of the tibial cutting block 12relative to the slope setting pin 14. In an embodiment, the biasing clip40 biases the slope setting pin 14 against an upper wall 50 thatdelineates an upper portion of the pin receiving slot 16.

The tibial cutting block 12 may be an additionally manufactured partmade of a polymeric material (e.g., nylon). However, other manufacturingtechniques and materials could be utilized to construct the tibialcutting block 12 within the scope of this disclosure.

Dependent, for example, on which section of the tibia requires cuts andwhether the left or the right tibia need treated, the tibia cuttingblock could look like the tibial cutting block 12 of FIGS. 2-6 . Thetibial cutting block could also have reversed left and right sides,whereas, for example, the first fixation pin hole 32 would be orientedat the right side of the block body 18, and the second cutting slot 30and the third fixation pin hole 36 would be oriented at the left side ofthe block body 18.

The slope setting pin 14 of the tibial cutting guide assembly of FIG. 1is further illustrated with reference to FIGS. 7-8 . The slope settingpin 14 may include a handle 52 and an elongated shaft 54 that extendsalong a longitudinal axis away from the handle 52.

The handle 52 of the slope setting pin 14 may be a curved handle. In anembodiment, the curvature of the handle 52 matches the curvature of thefront side 22 of the tibial cutting block 12. Together, the tibialcutting block 12 and the handle 52 may establish a gripping portion forergonomically handling the tibial cutting guide assembly 10 during use.

The elongated shaft 54 of the slope setting pin 14 may include aproximal section 56, a distal section 58, and a mid-section 60 betweenthe proximal section 56 and the distal section 58. The proximal section56 may connect at one end to the handle 52 and at an opposite end to themid-section 60 via a tapering portion 62. The proximal section 56 mayinclude a first diameter D1 that is smaller than a second diameter D2 ofthe mid-section 60. As further discussed below, the smaller firstdiameter D1 of the proximal section 56 allows the elongated shaft 54 tobe bent in order to reposition the slope setting pin 14 out of the pathof other instruments that may need to be inserted through the tibialcutting block 12.

The diameter D1 of the proximal section 56 of the elongated shaft 54 maybe configured such that the biasing clip 40 cannot bias the slopesetting pin 14 toward the upper wall 50 when the proximal section 56 ispositioned in the first cutting slot 28. The slope setting pin 14 istherefore more freely movable relative to the tibial cutting block 12when the proximal section 56 is positioned in the first cutting slot 28.In addition, the diameter D2 of the mid-section 60 of the elongatedshaft 54 may be configured such that the slope setting pin 14 is biasedby the biasing clip 40 when the mid-section 56 is positioned in thefirst cutting slot 28. The slope setting pin 14 is therefore less freelymovable relative to the tibial cutting block 12 when the mid-section 60is positioned in the first cutting slot 28. The ability to adjust thefirmness of the engagement of the slope setting pin 14 relative to thetibial cutting block 12 enables numerous advantages, including but notlimited to the ability to handle and maneuver the tibial cutting guideassembly 10 using only one hand.

The distal section 58 of the elongated shaft 54 may include ahook-shaped tip 64 at its end. The hook-shaped tip 64 may be insertedinto the joint space between the femur and the tibia and then be rotatedfor securing the slope setting pin 14 relative to the tibia.

The distal section 58 of the elongated shaft 54 may additionally includea pair of flat surfaces 66. The flat surfaces 66 help keep the slopesetting pin 14 from sliding medially or laterally with respect to thefemoral bone once the slope setting pin 14 is inserted into the jointspace between the femur and the tibia.

FIGS. 9-19 , with continued reference to FIGS. 1-8 , schematicallyillustrate an exemplary method for preparing a tibia 68 for receiving anarthroplasty implant. The method may be performed as part of anarthroplasty procedure. The unique design of the tibial cutting guideassembly 10 assists with tibial resection by providing patient specifictibial slope and level resectioning while providing for surgical controlover internal/external rotation and varus/valgus alignment. Fewer oradditional steps than are recited below could be performed within thescope of this disclosure, and the recited order of steps depicted inFIGS. 9-19 is not intended to limit this disclosure.

Referring first to FIG. 9 , while holding the side appropriate tibialcutting block 12 in the surgeon's hand as an extension of the handle 52of the slope setting pin 14, the elongated shaft 54 of the slope settingpin 14 may be inserted into the joint space between a patient's femur 70and the tibia 68. The elongated shaft 54 may be inserted at about themid-line of one of the femoral condyles 72 (in the illustratedembodiment, the femoral condyle 72 is the medial condyle of a rightknee). The slope setting pin 14 may then be rotated about 90 degrees inorder to position the hook-shaped tip 64 against a posterior surface 74of the tibia 68 (see FIG. 19 ). When properly inserted, the slopesetting pin 14 stabilizes the tibial cutting block 12 relative to thetibia 68 and also defines a native tibial slope as referenced by theanterior and posterior aspects of the tibia 68. The slope setting pin 14further establishes an appropriate tibial resection level by creatingspace (e.g., approximately 9 mm) from the posterior femur to the tibialresection.

Next, as shown in FIG. 10 , the tibial cutting block 12 may be movedinto contact with an anterior surface 76 of the tibia 68. For example,the tibial cutting block 12 may be slid along the elongated shaft 54 ofthe slope setting pin 14 toward the anterior surface 76 and may also berotated towards the midline of the tibia 68.

Once the tibial cutting block 12 is positioned as desired, a drop rod 78of a varus-valgus alignment guide 80 may be inserted through thealignment rod hole 38 of the tibial cutting block 12 (see FIG. 11 ). Thedrop rod 78 may then be utilized for achieving appropriate varus-valgusalignment of the tibial cutting block 12 relative to the tibia 68.

An angel wing tool 82 may optionally be utilized to ensure appropriateinternal/external rotation and medial/lateral positioning of the tibialcutting block 12, and more particularly the first and second cuttingslots 28, 30, relative to the tibia 68 (see FIG. 12 ). A prong 85 of theangel wing tool 82 may be inserted through the second cutting slot 30for adjusting the internal/external rotation of the second cutting slot30, and thus a vertical cutting path of the tibial cutting block 12,relative to the tibia 68.

Referring now to FIGS. 13 and 14 , the method may proceed by inserting afixation pin in the most accessible fixation pin holes of the tibialcutting block 12. In an embodiment, one fixation pin 84 is insertedthrough the second fixation pin hole 34 (see FIG. 13 ), and anotherfixation pin 86 is inserted through the third fixation pin hole 36 ofthe tibial cutting block 12 (see FIG. 14 ). However, the order ofinsertion and insertion location of the fixation pins 84, 86 are notintended to limit this disclosure.

Once satisfactory alignment of the tibial cutting block 12 has beenachieved, the proximal section 56 of the elongated shaft 54 of the slopesetting pin 14 may be bent in order to bend the handle 52 of the slopesetting pin 14 upwardly away from the tibial cutting block 12 (see FIG.15 ). An additional fixation pin 88 may then be inserted through thesecond fixation pin hole 34 (or any other fixation pin hole that has notyet been used). If still in place, the drop rod 78 and the angel wingtool 82 may be removed from the tibial cutting block 12 (see FIG. 16 ).

Referring now to FIGS. 17 and 18 , vertical and horizontal resectionscan next be made in the tibia 68 by inserting a saw blade 90 or othercutting tool through the first and second cutting slots 28, 30 of thetibial cutting block 12. The order of making the cuts is not intended tolimit this disclosure and could vary from surgery to surgery. Thefixation pins 86, 88 may act as a secondary guide for defining thecutting plane of the saw blade 90 when making the horizontal resectionsthrough the first cutting slot 28.

Once a complete resection has been performed, the hook-shaped tip 64 ofthe slope setting pin 14 and the fixation pins 84, 86, 88 may beutilized to facilitate removal of the resected portions of the tibialbone. Once all cuts are made and the resected portions removed, thearthroplasty procedure can proceed to any additional steps necessary forpreparing the joint for receiving one or more arthroplasty implants.

As alluded to above, the tibial cutting guide assembly 10 may be part ofan arthroplasty instrument set. For example, the tibial cutting guideassembly 10 could be packaged together as a kit with other surgicalinstruments, such as the varus-valgus alignment guide 80, the angle wingtool 82, the fixation pins 84-88, etc., for formulating the arthroplastyinstrument set.

Although the different non-limiting embodiments are illustrated ashaving specific components or steps, the embodiments of this disclosureare not limited to those particular combinations. It is possible to usesome of the components or features from any of the non-limitingembodiments in combination with features or components from any of theother non-limiting embodiments.

It should be understood that like reference numerals identifycorresponding or similar elements throughout the several drawings. Itshould further be understood that although a particular componentarrangement is disclosed and illustrated in these exemplary embodiments,other arrangements could also benefit from the teachings of thisdisclosure.

The foregoing description shall be interpreted as illustrative and notin any limiting sense. A worker of ordinary skill in the art wouldunderstand that certain modifications could come within the scope ofthis disclosure. For these reasons, the following claims should bestudied to determine the true scope and content of this disclosure.

What is claimed is:
 1. A tibial cutting guide assembly, comprising: atibial cutting block including a biasing clip; and a slope setting pinbiased toward a surface of the tibial cutting block by the biasing clip.2. The tibial cutting guide assembly as recited in claim 1, wherein theslope setting pin is adjustably received within a pin receiving slot ofthe tibial cutting block.
 3. The tibial cutting guide assembly asrecited in claim 2, wherein the surface is an upper wall of a block bodyof the tibial cutting block that delineates a portion of the pinreceiving slot.
 4. The tibial cutting guide assembly as recited in claim1, wherein a block body of the tibial cutting block includes a unitary,monoblock design and is comprised of a polymeric material.
 5. The tibialcutting guide assembly as recited in claim 1, wherein the tibial cuttingblock includes a first cutting slot and a second cutting slot that isseparated from the first cutting slot by an interior wall of the tibialcutting block.
 6. The tibial cutting guide assembly as recited in claim5, wherein a first fixation pin hole and a second fixation pin holeextend through the tibial cutting block and open into the first cuttingslot.
 7. The tibial cutting guide assembly as recited in claim 6,wherein a third fixation pin hole extends through the tibial cuttingblock and opens into the second cutting slot.
 8. The tibial cuttingguide assembly as recited in claim 1, wherein the biasing clip includesa first end portion integrally formed with an inner wall of a front sideof the tibial cutting block, a second end portion arranged adjacent toan inner wall of a tibial attachment side of the tibial cutting block,and an arced curvature between the first end portion and the second endportion.
 9. The tibial cutting guide assembly as recited in claim 1,wherein the biasing clip establishes a floor of a pin receiving slot ofthe tibial cutting block, and further wherein the slope setting pin ismovably received within the pin receiving slot.
 10. The tibial cuttingguide assembly as recited in claim 1, wherein the slope setting pinincludes an elongated shaft comprising a distal section portion thatincludes a hook-shaped tip and a pair of flat surfaces.
 11. The tibialcutting guide assembly as recited in claim 1, wherein the slope settingpin includes an elongated shaft comprising a proximal section, a distalsection, and a mid-section, and further wherein the proximal sectionincludes a first diameter that is smaller than a second diameter of themid-section.
 12. An arthroplasty instrument set, comprising: the tibialcutting block assembly of claim 1; a varus-valgus alignment device; andat least two fixation pins.